PORINA. 227 



The genus Tuhucellaria, D'Orhiguy, must rank in the 

 present group, with which it agrees entirely in the cha- 

 racter of the zooecium, though distinguished from the 

 other members by its articulated zoariura. 



Genus PORINA, D'Orbigny. 



Der. From Tropos, an opeiiiiig. 



EscHAUA (part.), auctt. 



BiDiASTOPORA (part.), D'Orbigiiy. 



PusTULiPORA (part.), M. Sars. 



Lepralia (part.), Busk. 



PoRiNA, D'Orbigny, Pal. Fran9. 1851 {mt Smitt). 



Onciiopora (part.), Busk. 



Quadricellakia, Sars {not D'Orbigny). 



Anarthropoka (part.), Smitt. 



Tessaradoma (sp.), Norman. 



Cylindroporella (sp.), Hincks. 



Generic Character. — Zocecia tubular or suhtubular 

 above, with a terminal circular orifice ; a median pore on 

 the front wall. Zoarium {in the British species) inc?'ust- 

 ing, or erect and ramose. 



As employed by D'Orbigny, the name Porina is re- 

 stricted to species with erect and branched zoaria, such as 

 our P. borealis ; but if the difference in habit between it 

 and P. tubulosa is not regarded as generic, we may very 

 properly give it a wider application, and make it cover the 

 larger group. This is the more allowable, as there is no 

 other available name which would be appropriate under 

 the circumstances. 



Porina borealis M^as originally described by Sars as a 

 Pustulipora. Subsequently (1863) he transferred it to 

 the Cheilostomata, to which it properly belongs, ' and 

 founded for its reception a new genus, Quadricellaria. 



q2 



